1. Field of the Invention
This invention relates to a torque transmitting clutch assembly and more specifically to a coupler and decoupler mechanism which is responsive to the angular acceleration of a rotating input member. Such a mechanism is useful for automotive vehicles.
2.Description of the Prior Art
One of the key components of any motor driven vehicle is a clutch which selectively couples or decouples a rotating input shaft with an output driven shaft. Clutches of this type have varying structures. One type of structure has a coil spring anchored to the input shaft frictionally engage a drum of the output shaft. One such device is shown in U.S. Pat. No. 1,640,472 to Starkey issued on Aug. 30, 1927. A variation of this coil spring clutch has the output shaft fit within the interior of a coil spring. The coil spring is wound tightly to frictionally engage the output shaft.
Another type of basic structure is the over-running clutch which an input shaft, output drum, and bearings circumferentially placed around the shaft between the shaft and drum. The bearings are wedged into a locked position when the input shaft is rotated in one direction. When the input shaft is rotated in an opposite direction or the output drum rotates faster than the shaft, the bearings disengage from the output shaft. Often the bearings are spring biased to the engaged position. Two such overrunning clutches are disclosed in U.S. Pat. No. 1,642,645 issued to Constantinesco on Sept. 13, 1927 and in U.S. Pat. No. 2,926,765 issued to Heid on Mar. 1, 1960. Overrunning clutches are often utilized in connecting the starter motor with an internal combustion engine.
Slip clutches have been designed to limit the amount of torque which can be transferred from the input shaft to the output shaft. When the torque is above a predetermined amount, slippage occurs which creates a loss of torque. Two such slip clutches are disclosed in U.S. Pat. No. 3,036,447 issued to Wilhelmsson et al on May 29, 1962 and U.S. Pat. No. 2,940,283 issued to Christenson et al on June 14, 1960.
Other types of clutches include a centrifugally actuated mechanism which causes the clutch to engage at a certain predetermined angular velocity of the input shaft by use of weights which are forced outwardly due to rotation of the input shaft. One such clutch is disclosed in U.S. Pat. No. 2,926,765 issued to Heid on Mar. 1, 1960.
No known clutch has been developed which responds, not to the speed to the input member, but to the angular acceleration of the input member. Such a clutch would be greatly advantageous in decoupling automobile accessories at critical times when the power of the engine should be concentrated in accelerating the forward motion of the vehicle. In addition, such a clutch would be greatly advantageous in a starter mechanism in an internal combustion engine which responds to the angular acceleration of the starter motor and automatically shuts off after the starter motor has started the internal combustion engine.